41,871 research outputs found

    Synthesis, characterization and urease inhibitory activities of Zn(II) complexes bearing C1-symmetric ligands derived from (R)-phenylethanamine

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    ABSTRACT. A series of Zn(II) complexes, supported with N-substituted phenylethanamine derivatives, [LnZnCl2] (where Ln = LA ((R)-1-phenyl-N-(thiophene-2-ylmethyl)ethanamine; LB (R)-N-(5-meyhylthiophene-2-yl)methyl-1-phenylethanamine; LC ((R)-N-(furan-2-ylmeththyl)-1-phenylethanamine and LD (R)-N-((5-methylfuran-2-yl)methyl)-1-phenylethanamine) were synthesized and characterized. The urease inhibitory activities of these complexes were determined against selected urease inhibitors where [LBZnCl2] was found to be the most prominent inhibitor of Jack bean urease (J. B. urease) (IC50 = 10.39±0.78 μM), whereas the activity of Bacillus pasteurii urease (B. P. urease) was predominantly inhibited by [LAZnCl2] (IC50 = 8.68±0.7 μM). Additionally, MOE-Dock program was used to affirm the probable binding modes of these complexes into the crystal structure of J. B. urease which certainly verified the inhibitory mechanism of these novel complexes.                     KEY WORDS: Zn(II) complexes, (R)-Phenylethanamine, Urease inhibition, Molecular docking   Bull. Chem. Soc. Ethiop. 2021, 35(2), 301-314. DOI: https://dx.doi.org/10.4314/bcse.v35i2.

    Anthropic tuning of the weak scale and of m_u/m_d in two-Higgs-doublet models

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    It is shown that in a model in which up-type and down-type fermions acquire mass from different Higgs doublets, the anthropic tuning of the Higgs mass parameters can explain the fact that the observed masses of the dd and uu quarks are nearly the same with dd slightly heavier. If Yukawa couplings are assumed not to "scan" (vary among domains), this would also help explain why the t quark is much heavier than the b quark. It is also pointed out that the existence of dark matter invalidates some earlier anthropic arguments against the viability of domains where the Standard Model Higgs has positive μ2\mu^2, but makes other even stronger arguments possible.Comment: 31 pages, 7 figure

    Deformable subreflector computed by geometric optics

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    Using a Cassegrainian geometry, the 64-meter antenna with its distorted paraboloidal reflecting surface is forced to produce a uniform phase wavefront by a pathlength-compensating subreflector. First, the computed distortion vectors at the joints or nodes of the main reflector structure supporting the surface panels are best fitted to a paraboloid. Second, the resulting residual distortion errors are used to determine a compensating subreflector surface by ray tracing using geometric optics principles. Third, the totally corrected subreflector surface is defined by the normal directions and distances to the surface of the original symmetric hyperboloid for the purpose of evaluation. Finally, contour maps of distortions of the paraboloid reflector and the compensating subreflector are presented. A field-measured check of the subreflector in focused position as computed by the described methodology is also presented for the antenna position at horizon look with the geometry at 45 degrees elevation

    Client Satisfaction Towards Quality of Health Services: an Assessment at Primary Healthcare of District Gujranwala

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    This survey designed to evaluate the satisfaction level and the factors that affect the patient satisfaction regarding health care delivery services with the aim to improve the services in the primary health care settings of Gujranwala. A Cross Sectional Study done on randomly selected patients attending the basic health units of Gujranwala, with more than18 years of age. Pretested structured "Liker scale questionnaire" was used for data collection. Out of total respondents, 62 (41.3%) clients were satisfied with the services provided by the basic health units of Gujranwala. The factors identified to determine patient satisfaction were accessibility of services, behavior of staff, health education, level of cleanliness, drug availability and miscellaneous services. Not a single ranked area of satisfaction noticed. Client\u27s occupation and income had significant relationship with the patient satisfaction level. Gender, age, and education of clients were not contributing factors; they not affect the client satisfaction level.Less than half clients were satisfied with the services provided by the basic health units. Management of health facilities needs to improve the services

    Callus induction via different growth regulators from cotyledon explants of indigenous chick pea (Cicer arietinum L.) cultivars KK-1 and Hassan-2K

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    Callus induction from cotyledon explants was studied in indigenous chick pea (Cicer arietinum L.) cultivars KK-1 and Hassan-2K on MS and B5 media containing different combinations and concentrations of growth regulators. Different MS and B5 callusing media containing varying level of 2, 4-D (2 and 4 mg/l), NAA (0.50 and 1 mg/l), BAP (5 and 10 μM) and their combinations were tested for callus induction response. Percent callus and callus fresh weight (g) were recorded after two and four weeks of culture for both genotypes. For KK-1 cultivar, the maximum callus frequency (71 and 97%) followed by (65 and 96%) were observed on 4 mg/l 2,4-D+5 μM BAP in MS and 4 mg/l 2,4-D in B5 media, respectively after two and four weeks of culture. Similarly, the highest callus fresh weight (0.411 and 0.787 g) were also recorded for MS+4 mg/l 2,4-D+5 μM BAP in contrast to B5 where the highest callus weight (0.401 and 0.693 g) was achieved on 4 mg/l 2,4-D only. In Hassan -2K, the highest callus % (68 and 96) and fresh weight (0.572 and 0.821 g) were recorded on MS+4 mg/l 2,4-D+0.50 mg/l NAA after two and four weeks of culture, respectively. In B5 medium, 2,4-D+BAP combination produced average callus induction response for both cultivars.Key words: Callus induction, chick pea cotyledons, growth regulators

    Phyto-agglutinin, total proteins and amino assimilating enzymatic activity of indigeneous chickpea (Cicer arietinum L.) cultivars

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    Biochemical studies were carried out with in vitro micropropagated plantlets of two indigenous cultivars of chickpea (Cicer arietinum L.), KK-1 and Hassan-2K, where extract from shoots, leaves, roots, and reproductive organs were determined for human erythrocyte agglutination (by mixing the lectin containing extract 1:1 with a 2% erythrocyte suspension), protein profiling and the amino assimilating (glutamine synthetase) enzymatic activity. Both of KK-1 and Hassan-2K cultivars extract showed highly phyto-agglutination of human erythrocytes with reproductive organs and other tissues, which represents the presence of potent lectins (phyto-agglutinin). The amino assimilating enzymatic activity of green leaves of Hasan-2K was found higher (3.545 GS μmol.gfw-1.min-1) as compared to KK-1 (2.873 GS μmol.gfw-1.min-1). Protein content profile showed variation in bulk proteins of various tissues, higher (12.634 μg/gfw) and (2.987 μg/gfw) in reproductive organs of KK-1 and Hasan-2K, respectively.Key words: Chickpea, glutamine synthetase, glyco-protein, lectin, phyto-agglutinin
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